Brake



8 1944' J. A. FORBES 2,355,720

BRAKE Filed Jan. 14, 1943 2 Sheets-Sheet 1 INVENTOR.

JOSEPH A. FORBES ATTORNEYS Aug. 15, 1944.

1.1. A. FORBES BRAKE Filed Jan. 14, 1945 2 Sheets-Sheet 2 INVENTOR.

JOSEPH A. FORBES ATTORNEYS Patented Aug. 15, 1944 BRAKE Joseph A.Forbes, Detroit, Mich.', assignor to "John Snead, Royal Oak, Mich.

Application January 14, 1943, Serial No. 472,381 Claims. T (CI.188-79l5) The invention relates to brakes and refers more particularlyto brakes of that type having brake members relatively movable axiallytoward i I each other to apply the brake.

The invention has for one object to provide an improved brake of theabove type having automatically adjustable means for normally main,taining a predetermined clearance betweenthe brake members.

The invention has for another of its objects to so construct the brakethat its automatically adthe frusto-conical disc portion l1 and theaxially extending flange 03 extending-in an inboard direction from theouter edge of the disc portion. The non-rotatable outboard and inboardbrake members 6 and I, respectively, are in the nature of discs havingfrusto-conical disc portions IO to which the linings 8 are secured andthe subjustable part for normally maintaining the predeterminedclearance is subject to but very little friction while being adjusted.

These and other objects of the invention will become apparent from thefollowing description, taken in connection with the accompanyingdrawings, in which Figure 1 is an inboard elevation partially brokenaway and in section of a brake embodying the invention;

Figures 2 and 3 are cross sections on the lines 2--2 and 33,respectively, of Figure l; v

As illustrated in the present instance the brake is applied to. anairplane landing wheel, although it is. apparent that it'may'beotherwise used as with motor vehicle wheels. The brake comprises themain brake mechanism l and the pilot brake mechanism 2 for applying themain brake mechanism.

The main brake mechanism comprises the ro-v tatable outboard,intermediate and inboard friction elements or brake members 3, 4 and 5,respectively, and the non-rotatable outboard, and inboard frictionelements or brake members 6 and 1, respectively, which preferably havesecured to their opposite sides the brake linings 8. The rotatableoutboard brake member 3 is cup-shaped and has the frusto-conical discportion 9, the annular wall l0 extending in an inboard direction fromthe outer edge of the disc portion and the radial back II at the inneredge of the disc portion, the latter being suitably se- V merit ring 35.

cured to the landing wheel as by means of the bolts I2 and the nuts l3.The annular wall I 0 is formed with the. axially extending openings [4into which project radial projections at the I outer edge of therotatable, intermediate brake member 4. The annular wall Ill is alsoformed with the enlargement it which is located in an inboard directionfrom the openings I4 and encircles and pilots the rotatable inboardbrake member 5. The rotatable intermediate brake member 4 is in thenature of a frusto-conical disc. The rotatable inboard brake member 5has 1 tion.

stantially radial central portions 20, each of which latter is formedwith an annular series of holes 2| for slidably engaging the-studs 22which extend inan outboard direction from the radial flange 23 of thesupport 24 having the shaft 25 on whichis journaled the airplane landingwheel 26.

21 are channel-shaped links, preferably formed of spring steel,operatively connecting the rotatable outboard and inboard brake members3 and 5, respectively. The links exten'd substantially axially in thenormal or off positions of the parts and are angularly spaced at equaldistances from each other about the annular wall it of the rotatableoutboard brake member 3 and the axially extending flange iii of therotatable inboard brake member 5. Each link is provided at its outboardend with the radially inwardly extendin'g portion 28, which extendsthrough an opening 29 in the, annular wall in and abuts the inboard endof the opening. The portion 23 is formed with the lateral projections 30which extend circumierentiallyinside the annular wall l0 beyond theopenings 29 to thereby retain the outboard ends of the links fromaccidental disengagement from the annular wall. Each link is provided atits inboard ,end with the radially inwardly extending portion 3| whichextends through the opening 32 in the axial flange l8 of the rotatableinboard brake member 5, the opening preferably being open in an inboarddirec- The portion '3l also extends through the opening 33 in the axialflange 34 of the abut- The axial flange 34 isone of an annular series ofprojections and extends within the axial flange I8. frictionally securedin place by the angularly spaced bowed springs 36 which frictionallyabut the radially inner faces of different axial flanges 34 and areadjustably clamped in place by the nuts 31 threaded upon the bolts 38,which extend through the axial flanges 34 and I8 and preferably haveheads located in countersinks in the radially outer faces of the axialflanges 18. The bolts 38 are angularly spaced at equal distances aroundthe axial flange l8 and the openings 39 in the axial flanges 34 of theabutment ring through which the bolts pass preferably open in Theabutment ring is ring. outboard ends of the openings arepredeterminediorthe' purpose of securing predetermined clearance between therotatable brake members and "to the slot the parts may be readilyassembled by a relative "an outboard" direction to permit the abutmentring to be assembled with the rotatable inboard brake memberbya'relative axialmovement. 40 is'a sheet 'metal annular guard having aradial flange secured" to the radialflangefl oi. theabut- I -mentringyby suitable means, such as screws.

The guard -has'an axialflange which is radially outwardly *spaced fromthe rotatable inboard brakemember andwhich also encirclesthe inboard endportions of the links 21 tohold the same from accidental disengagement.42 arecoil springs located circumierentially between the links 21 andhaving their opposite ends respectively connected to the rotatableoutboard and inboard brake members 3 and 5, respectively, to

resiliently hold the same in normal or off .positions, at which time thelinks 21 extend axially.

Each-spring 42 at its inboard end abuts the radialflange of the annularguard) and at its outboardvend abuts the web of a sheet metal clip '43into which the outboard end of the spring ex- :33 in the axial flanges34 of the abutment. ring have their inboard ends formed with the sameinclination as the portionsll and the cams 46. while theiroutboard endsare formed to extend parallel to the radial flange of the abutment Thedistances between the inboard and the non-rotatable brake members whenin their normal or oilpositions and also for the purpose 30f securingalimited angularmovementof the links during. operation of the brake.

'To' resiliently urgethe cam ring 44 circumferentially in aidirection'to maintain the cams 46 normally against the inboard portions3| of the links 21 when the parts are in their normal or o'if positionslhave provided the diametrically opposite coilisprings 41, eachof whichis con nected atone, end to the plate secured to a bolt 38 and at theother end to the bracket 43 which is riveted to the camv ring betweenadjacent axial flanges 34 of the abutment ring'and is slidable in thecircumferentially extending "slotjllformed in the axial flange l8 of therotatable inboard brake member.

The axial flange I8 is also provided with a transverse 'slot 5i=whichleads from the'inboard edge of the flange 50, the'constructionbeing such that axial movement. 7

The pilot brake mechanism 2 comprises the rotatable brake drum 52 andthe friction element 5 53 engageablewith the cylindrical radially innerfriction face of the drum. The drum extends in an inboard direction fromthe radially inner edge of the rotatable inboard brake member sand ispreferably integral therewith. The friction ele rnent 53 comprises brakeshoes, which are car- "ried by the non-rotatable inboard brake member 1.The shoes are adapted to be anchored by the anchor pins 54 which aresecured to-the non- "rotatable inboard brake member 1 and the shoes areadapted to be actuated by the diametrically opposite fluid pressureoperated actuators or wheel cylinders 55 which are positioned betweenand are carried by the end portions of the shoes.

.21 and the coil springs 42 with the links extending axially. Ifthe-rotatable inboard brake member? 5. is retarded by means of the pilotbrake mechanism '2 through the application of the friction element 53 tothe drum 52 the links 21 are compelled to move angularlyor swing aboutthe cam ring 44 as a fulcrum. These links compel the rotatable inboardbrake member to move against the non-rotatable inboard brake memherwhich in turn is moved against the rotatable vlar or swingingintermediate brake member which is then moved against thenon-rotatableoutboard brake member, which latter is finally movedagainst the rotatable outboardbrake member, completing the applicationof the main brake mechanism. If the angular positions of the links 21,as shown by the dotted line 56 in Figure 3, are such that the inboardportions 3| of the links contact the inboard ends of the openings 33 inthe axial flanges -34 of the abutment ring the latter is moved in aninboard direction relative to the axial flange l8 of the rotatableinboard brake member 5. Then when the braking pressure exerted on thepilot brake mechanism is removed the bowed springs 38 serve to hold theabutment ring 35 in its adjusted position relative to the rotatableinboard brake'member 5 and the 'coil springs 42 serve to move theabutment ring and the rotatable inboard brake member away from therotatable outboard brake member 3 to a predetermined position asdetermined by the links 21 engaging the outboard ends of the openings 33in the axial flanges of the abutment ring. As the pressure of theinboard portions 3| of the links21 on the cams 43 of the cam ring isremoved or sufficiently decreased, the coil springs 41 act on the camring 44 to circumferentially move the same in the direction of thearrows of Figures 1 and '3 to move its cams 46 against the inboardportions 3i of the links 21, there being but little friction opposingthis At this time the automatic brake adjustment is completed and apredetermined clearance is provided between the rotatable andnon-rotatable brake members of the main brake mechanism. Also; theadjustment is such that the brake members of the main brake mechanismcan be moved into braking engagement by the links 21 and cam ring 44with the links having an angumovement within a predetermine angle tomaintain the desired high operating efficiency.

What I claim as my invention is:

1.'A brake comprising brake members relatively movable toward eachother, a brake memprising links and an automatically adjustable camringcooperating with said links to normally maintain a predeterminedclearance bemovement of the cam ring.

tween said first mentioned brake members and said second mentioned brakemember.

2. A brake comprising rotatable brake members relatively movable towardeach other, a nonrotatable brake member between and engageable with saidfirst mentioned brake members upon relative movement toward each other,means comprising links and a cam ring for relatively moving said firstmentioned brake members toward each other upon retardation of one ofsaid first mentioned brake members, means comprising an abutment memberand springs for relatively moving said first mentioned brake membersaway from each other, and spring means for adjustably positioning saidcam ring relative to said links.

3. A brake comprising rotatable brake members relatively movable towardeach other, a non-rotatable brake member between and engageable withsaid first mentioned brake members upon relative movement toward eachother, means comprising a cam ring and links for relatively moving saidfirst mentioned brake members toward each other upon retardation of oneof said first" mentioned brake-members, an abutment ring adjustablysecured to said one of said first mentioned brake members in a positionpredetermined by said links, yieldable members between said abutmentring and'the other of said first mentioned brake members for relativelymoving said first mentioned brake members away from each other, andspring means for yieldably positioning said cam ring relative to saidlinks.

7 between said first mentioned brake members and 4. A brake comprisingbrake members relatively movable toward each other, a brake memberbetween'and engageable with said first mentioned brake members uponrelative movement toward each other, means comprising links and a cammember ,for relatively moving said first mentioned brake members towardeach other upon relative rotation thereof, means comprising an abutmentmember and spring means for relatively moving said first mentioned brakemembers away from each other, said abutment member being engageable bysaid links to predeterminedly position said abutment member on one ofsaid first mentioned brake members, and means connected to said cammember for adjustably positioning the same relative to said links.

5. A brake comprising brake members relatively movable toward eachother, a brake member between and engageable with said first mentionedbrake members upon relative movement toward each other, means forrelatively moving said first mentioned brake members toward each otherupon relative rotation thereof, said means comprising links and cammeans cooperating with said links, said cam means being adjustable tonormally maintain a predetermined clearance said second mentioned brakemember, spring means for adjusting said cam means, and means forrelieving said cam means from pressure by said links during adjustmentof said cam means.

JOSEPH A. FORBES.

